The Hepatitis A Vaccine

What It Is and What It Protects Against

Hepatitis is a liver disease that can be caused by the hepatitis A virus (HAV). The virus is spread through close contact and can be spread by eating or drinking HAV-contaminated food or water. The HepA vaccine is recommended for all children at age one.

General Use 

Hepatitis A can be passed within the same household and hospitalizes one out of five infected individuals. To protect against this disease, the following people are advised to get the HepA vaccine:

• children aged one
• anyone (including infants and children) traveling to countries with high rates of HepA
• children and adolescents who live in communities with high risks or outbreaks of HepA
• people with chronic liver disease
• people who work with HAV-infected primates
• people who work with HAV in laboratories

Dosage:

• First dose: between 12 to 23 months old
• Second dose: 6 months following first dose

Who Should Not Get It

While the CDC recommends some people to receive routine HepA vaccinations and also advises the vaccine for individuals traveling to high-risk areas (including Mexico, Central and South America, Africa, parts of Asia, and eastern Europe), there are certain people who should not get this vaccine. Risk factors include:

• past severe reaction to HepA vaccine
• severe allergy to component(s) of the HepA vaccine (this vaccine contains the chemical alum, and some HepA vaccines have 2-phenoxyethanol)
• anyone who is moderately to severely ill is advised to wait until a full recovery before getting vaccinated
• pregnant women, though considered at a low risk, are advised to consult with their doctor to determine if this vaccine is safe
• Also, there are many people who have already been exposed to hepatitis A and therefore have immunity to the disease. If you are an adult considering a vaccination, it is reasonable to have your blood checked to see if there is evidence that you have already had hepatitis A, so do not need the shot.

Potential Side Effects

Though the risk of serious harm from this vaccine is small compared with the actual untreated disease, the vaccine does hold some risk, from mild to severe side effects.

Mild side effects include:

• soreness where the shot was given
• headache
• loss of appetite
• tiredness

Severe side effects include:

• serious allergic reaction, anywhere from minutes to a few hours after receiving the shot